Birds and the Salton Sea

An exploration of the importance of the Salton Sea and associated ecosystems to birds: a

global and regional perspective

Presented to: California Water DialogueSept. 16, 2003Los Angeles

Daniel S. Cooper, M.Sc. (University of California, Riverside)

Director of Bird ConservationAudubon CaliforniaPasadena

Birds and the Salton Sea

Habitat diversity in the Lower Colorado River Valley (“LCR”) ecosystem

Rare vs. rare Defining the Salton Sea avifauna (=

birdlife) Outlook for Salton Sea avifauna, and

what Audubon is doing to help

Key bird habitats of the Salton Sea/LCR Valley (in no order)

Shallow, open water– Salton Sea, northern Gulf of California

Islands Freshwater/brackish marsh

– LCR and tribs.; seeps in large canals; unlined smaller canals Mudflat/Impoundment

– Mainly South End Salton Sea Mesquite Bosque

– Algodones Dunes, Lower Colorado River Valley Cottonwood/Willow Woodland

– Lower Colorado River Valley, Locally in Imperial Valley Agricultural fields

– Mainly Imperial and Mexicali Valleys; locally elsewhere

Rare vs. “rare”

Species formerly common in California, now declining or lost entirely– Generally due to habitat loss– e.g. Burrowing Owl, Mountain Plover

Species formerly absent or in low numbers; now present but still rare– Due to habitat alteration or climate/global change– e.g. Gull-billed Tern

Species never common in California, and only occurring as vagrants– Chased by bird-watchers; of low conservation concern

The Salton Sea avifauna

Lower Colorado River (“LCR”) Endemics “Last Stand” breeders/winterers Winter congregants Summer dispersers Passage migrants Vanishing (vanished?) nesters

Lower Colorado River “Endemics”

Confined to extreme northwestern Mexico, western AZ, southern NV and southeastern CA– “Yuma” Clapper Rail– “Van Rossem’s” Gull-billed Tern– Abert’s Towhee– “Salton Sea” Song Sparrow– “Large-billed” Savannah Sparrow

Clapper RailGull-billed Tern

“Last Stand” Breeders/Winterers

Mountain Plover– 30-40% Global population in

Imperial Valley (formerly widespread)

Burrowing Owl– 70% of California pop. in Imperial Valley– Associated with agricultural fields– 60% of CA population lost in 1980s

Western Snowy Plover– Largest wintering concentration in

interior of U.S.– Major interior-U.S. breeding site

Winter congregants

Begin arriving late July/August – November

Occur in two main roles:– Agricultural fields

Largest agricultural/grassland area in southern California

– The Salton Sea itself Largest and shallowest body of water in California

Winter congregants… (agricultural)

From left: Sandhill Crane, Long-billed Curlew, White-faced Ibis

Bob Miller

One of just 3 crane wintering areas left in SoCal (formerly common)

20K+ curlews wintering each year

40K ibis wintering each year

Winter congregants… (the Salton Sea itself)

David Blevins

Bob Miller

Up to 75% of N. Am. pop. passes through in early spring (from Gulf of CA to Great Basin)

1.5 million birds in winter

“Lost” shallow water lakes: Tulare Lake, Owens Lake, San Jacinto LakeBuena Vista Lake; plus most coastal wetlands south of SF Bay…

Winter congregants… (the Salton Sea itself)

David Blevins

Bob Miller

100+ miles of shoreline

10s of thousands of shorebirds on shoreline and adj. impoundments

30% of Global AWP pop.

“Lost” shallow water lakes: Tulare Lake, Owens Lake, San Jacinto LakeBuena Vista Lake; plus most coastal wetlands south of SF Bay…

Black-necked StiltAm. White PelicanAmerican Avocet

And lots in between…

David Blevins

Bob Miller

Freshwater impoundment at the edge of the Sea (southeast corner)

c. 30,000 Snow and Ross’ Geese

100,000+ other waterfowl

Richard Ditch

Summer Dispersers: north out of the Gulf

Large-billed Savannah SparrowYellow-footed Gull, Brown Pelican

(Looking south)

Passage migrant songbirds

Spring: Along eastern Gulf of California and directly through Salton Trough

Fall: In hills west and east of Salton Trough

Extensive use of native riparian and mesquite

habitat

Vanishing (from CA) species

Harris’ Hawk

Fulvous Whistling-DuckElf Owl

Vanishing (from CA) species

• Elf Owl• Formerly common along LCR – now 1-5 pr. (if still breeds)• Most of habitat cleared for agriculture

• Harris’ Hawk• Extirpated from Imperial Valley c. 1955, from LCR (CA) c. 1965

• Fulvous Whistling-Duck• Formerly (pre-1950) bred throughout southern Calif. wetlands• Fairly common at South End Salton Sea Impoundments until 1990s

Outlook for the Sea

“Do nothing” (Increased salinity/pollutants = fewer fish) Declines in pelicans Unhealthy birds?

– Lower Colorado River continues to dry/degrade “Save” the Sea w/o retaining some agriculture

– No more Burrowing Owl, Sandhill Crane, curlews, etc. Audubon is pushing for maximum restoration of entire

LCR system, including the Salton Sea– Improvement to threatened ecosystems– Reflective of historic conditions– No “net loss” of birds– No increase of exotic vegetation

Thanks!

Audubon California is the state office of the National Audubon Society. Formally established in 1996, it has its own Board of Directors and staff; manages >10,000 acres of centers and lands throughout the state; and raises 100% of its operating funds.